1. Field of the Invention
This invention relates to a method for measuring an integrated weight of a particulate material in a given prior period of time while the particulate material is being continuously fed to a powder treating system or the like.
2. Description of the Prior Art
There are known in the art various feed mechanisms for particulate or powdery materials (hereinafter referred to simply as "powder" for brevity), of which the systems utilizing fluid pressure have a number of advantages over gravitational or mechanical feed systems, including a longer transfer distance of the particulate material and a continuous quantitative feed capability. A powder transfer over a long distance, however, gives rise to large pressure losses in the feed line, necessitating feeding the material under an extremely high pressure especially in a case where a high pressure operation is intended at the end of the feed line, under a pressure in excess of the pressure on the receiving side in consideration of the pressure losses. In such a case, it becomes necessary to raise the pressure of the carrier gas source and to increase the internal pressure of the powder feed container which delivers the particulate material, in addition to the necessity of providing a powder replenishing container for replenishing the particulate material to the powder feed container and desirably a container for holding a stock of the particulate material for supply to the replenishing container. The particulate material is thus fed successively from the stock container to the replenishing container (hereinafter referred to as "stock feed"), from the replenishing container to the feed container (hereinafter referred to as "powder replenishment") and from the feed container to a powder treating system (hereinafter referred to as "powder feed"). Moreover, it is the general practice to feed the stock powder under ambient pressure while intermittently pressurizing the replenishing container, said container continuously feeding powder under pressure, each time replenishment of the feed container occurs so that a relatively complicated pressure control process is involved in the transfer of the particulate material. However, there has been known no method or means for accurately measuring the weight of the particulate feed material flowing along the aforementioned routes such as, for example, a method for accurately measuring the total weight of a particulate material which was fed in a given prior period of time, making it difficult to improve the accuracy of operation control on the side of the powder treating system.